Control cage assembly for centrifugal blast wheel machine

ABSTRACT

A centrifugal blast wheel machine includes a wheel assembly, an impeller positioned about an axis of the wheel assembly, a motor coupled to the impeller to drive the rotation of the impeller and the wheel assembly, and a control cage assembly surrounding the impeller and secured to the wheel assembly. The control cage assembly includes a control cage and a locking ring secured to a peripheral edge of the cylindrical wall. The locking ring includes an indicator projecting radially outwardly from the locking ring, and an adaptor plate secured to the wheel assembly. The adaptor plate includes at least one recess formed therein to receive the indicator when securing the locking ring and the control cage to the adaptor plate. The adaptor plate further includes a retaining ring secured to the adaptor plate to firmly secure the locking ring and the control cage in place.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

The present disclosure relates generally to abrasive blast wheels andmethods for cleaning or treating surfaces of work pieces, and moreparticularly to a control cage assembly for a centrifugal blast wheelmachine and to methods of assembling centrifugal blast wheel machines.

2. Discussion of Related Art

Centrifugal blast wheel machines generally include a rotatable wheelhaving a plate or a pair of spaced plates that carry radially extendingblades. Particulate matter is discharged from a center of the blastwheel onto rotating surfaces of the blades, which propel the particulatematter against surfaces of a work piece to be cleaned or treated.Specifically, blast media is fed from a feed spout into a rotatingimpeller situated within a control cage at the center of the blastwheel. The media is fed from the impeller, though an opening in thecontrol cage, and onto the heel or inner ends of the rotating blades.The media travels along the faces of the blades and is thrown from thetips of the blades at the work piece surfaces to be treated.

In certain embodiments, unwanted media blasts directed towards a housingof the centrifugal blasting wheel machine can harm a liner systemprovided on the housing. There is a need for a system to preventaccidental blasting into the housing that cause potential failures inthe liner system as witnessed with conventional cast liner.

SUMMARY OF THE DISCLOSURE

One aspect of the disclosure is directed to a centrifugal blast wheelmachine comprising a wheel assembly having a plurality of bladesconfigured to throw blast media introduced into the wheel assemblyagainst a work piece, and an impeller positioned about an axis of thewheel assembly. In one embodiment, the impeller has a media inlet at oneend adapted to receive blast media and a plurality of impeller mediaoutlets constructed and arranged to allow egress of blast media uponrotation of the impeller. The machine further comprises a motor coupledto the impeller to drive the rotation of the impeller and the wheelassembly, and a control cage assembly surrounding the impeller andsecured to the wheel assembly. The control cage assembly includes acontrol cage having a cylindrical wall defining an interior chamber anda media outlet formed in the cylindrical wall to allow the egress ofblast media from the interior chamber, a locking ring secured to aperipheral edge of the cylindrical wall, the locking ring including anindicator projecting radially outwardly from the locking ring, and anadaptor plate secured to the wheel assembly. The adaptor plate includesa central opening configured to receive the cylindrical wall of thecontrol cage therein and at least one recess formed therein configuredto receive the indicator when securing the locking ring and the controlcage to the adaptor plate. The adaptor plate further includes aretaining ring configured to be secured to the adaptor plate and tofirmly secure the locking ring and the control cage in place.

Embodiments of the machine further may include the adaptor plate havinga circumferential recess formed therein. The circumferential recess maybe configured to receive the locking ring therein. The at least onerecess of the adaptor plate may extend outwardly from thecircumferential recess. The at least one recess may include a range ofmovement of the control cage within the locking ring. The range ofmovement may be color coded. The at least one recess further may act asa positive stop for the indicator needle to prevent further rotationalmovement of the locking ring beyond a recommended setting. The lockingring may freely float between the retaining ring and the adaptor plateuntil the retaining ring is secured in place.

Another aspect of the disclosure is directed to a control cage assemblyfor a centrifugal blast wheel machine. In one embodiment, the controlcage assembly comprises a control cage having a cylindrical walldefining an interior chamber and a media outlet formed in thecylindrical wall to allow the egress of blast media from the interiorchamber, and a locking ring secured to a peripheral edge of thecylindrical wall. The locking ring includes an indicator projectingradially outwardly from the locking ring. The control cage assemblyfurther comprises an adaptor plate secured to the wheel assembly. Theadaptor plate including a central opening configured to receive thecylindrical wall of the control cage therein and at least one recessformed therein configured to receive the indicator when securing thelocking ring and the control cage to the adaptor plate. The control cagefurther comprises a retaining ring configured to be secured to theadaptor plate and to firmly secure the locking ring and the control cagein place.

Embodiments of the control cage further may include the adaptor platehaving a circumferential recess formed therein. The circumferentialrecess may be configured to receive the locking ring therein. The atleast one recess of the adaptor plate may extend outwardly from thecircumferential recess. The at least one recess may include a range ofmovement of the control cage within the locking ring. The range ofmovement may be color coded. The at least one recess further may act asa positive stop for the indicator needle to prevent further rotationalmovement of the locking ring beyond a recommended setting. The lockingring may freely float between the retaining ring and the adaptor plateuntil the retaining ring is secured in place.

Yet another aspect of the disclosure is directed to a method ofassembling a centrifugal blast wheel machine. In one embodiment, themethod comprises: providing a control cage having a cylindrical wallhaving an interior chamber and a media outlet formed in the cylindricalwall to allow the egress of blast media from the interior chamber;securing a locking ring to a peripheral edge of the cylindrical wall,the locking ring including an indicator projecting radially outwardlyfrom the locking ring; securing an adaptor plate to the wheel assembly,the adaptor plate including a central opening configured to receive thecylindrical wall of the control cage therein and at least one recessformed therein configured to receive the indicator when securing thelocking ring and the control cage to the adaptor plate; positioning thecontrol cage having the locking ring on the adaptor plate, and securinga retaining ring to the adaptor plate to secure the locking ring and thecontrol cage in place.

Embodiments of the method further may include the adaptor plate having acircumferential recess formed therein, the circumferential recess beingconfigured to receive the locking ring therein. The at least one recessfurther may include a range of movement of the control cage within thelocking ring. The range of movement may be color coded. The at least onerecess further may act as a positive stop for the indicator needle toprevent further rotational movement of the locking ring beyond arecommended setting. The locking ring may freely float between theretaining ring and the adaptor plate until the retaining ring is securedin place.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are not intended to be drawn to scale. In thedrawings, each identical or nearly identical component that isillustrated in various figures is represented by a like numeral. Forpurposes of clarity, not every component may be labeled in everydrawing. In the drawings:

FIG. 1 is a perspective view of a portion of a centrifugal blast wheelmachine;

FIG. 2 is another perspective view of the centrifugal blast wheelmachine;

FIG. 3 is an exploded perspective view of the centrifugal blast wheelmachine;

FIG. 4 is a perspective view of a feed spout having a clamp;

FIG. 5 is a perspective view of a control cage assembly of the presentdisclosure;

FIG. 6 is another perspective view of the control cage assembly;

FIG. 7 is a front view of the control cage assembly;

FIG. 8 is a cross-sectional view of the control cage assembly;

FIG. 9 is an exploded perspective view of the control cage assembly; and

FIG. 10 is an enlarged front view of an indicator or the control cageassembly.

DETAILED DESCRIPTION

Embodiments of the present disclosure are directed to a control cageassembly configured to permanently indicate a correct blast pattern(also called “hot spot”) through a control cage as set by themanufacturer. The control cage assembly further is configured to preventan incorrect blast pattern setting through the control cage as currentlypossible on existing control cage designs. The control cage assembly isdesigned to prevent inaccurate settings when locking the control cage inplace.

The control cage assembly further prevents substandard blast wheelperformance resulting from the incorrect user setting of the controlcage/hot spot. This is achieved by providing a color coded referencepoint into a specific area that is machined or recessed in a controlcage adaptor plate combined with the indicator attached to (or machinedin) a locking ring. The assembly includes an outer control cageretaining ring fixed to the control cage adaptor plate on which thecontrol cage is fixed into the control cage locking ring. The lockingring will freely float between the retaining ring and the adaptor plateuntil at such time the retaining ring is fastened into place applyingpressure on the locking ring, securing it and the control cage intoplace. A noted feature of the control cage assembly is the indicatorneedle attached onto the locking ring that will be nested into the colorcoded recess formed in a control cage adaptor plate. The color codedrecess further acts as a positive stop for the indicator needle toprevent further rotational movement of the locking ring (which controlsthe control cage) beyond a recommended setting.

Referring to the drawings, and more particularly to FIGS. 1-3, acentrifugal blast wheel machine is generally indicated at 10. In oneembodiment, the centrifugal blast wheel machine 10 includes a housing,generally indicated at 12, which is designed to house the components ofthe centrifugal blast wheel machine. The centrifugal blast wheel machine10 further includes a rotating impeller 14 supported by the housing 12,a control cage assembly, generally indicated at 16, which surrounds theimpeller, and a wheel assembly, generally indicated at 18, whichreceives the control cage assembly. A motor 20 is provided to drive therotation of the impeller 14 and the wheel assembly 18. The arrangementis such that blast media is fed from a feed spout into the rotatingimpeller 14, which is driven by the motor 20. By contact with vanes ofthe rotating impeller 14 (as well as with other particles of mediaalready in the impeller), blast media particles are accelerated, givingrise to a centrifugal force that moves the particles in radialdirection, away from the axis of the impeller. The particles, now movingin a generally circular direction as well as outwards, move throughopenings formed in the impeller 14 into a space between the impeller anda control cage of the control cage assembly 16, still being carried bythe movement of the impeller vanes and the other particles.

When the particles that have passed though the impeller openings intothe space between the impeller 14 and the control cage reach an openingprovided in the control cage, rotational and centrifugal forces move theparticles through the opening and onto ends of the vanes. The controlcage assembly 16 functions to meter a consistent and appropriate amountof blast media onto the blades of the wheel assembly 18. As the vanes ofthe impeller 14 rotate, the particles are moved along their lengths andaccelerate until they reach the ends of the vanes and thrown from theends of the vanes. Although the impeller 14 is shown to be cylindricalin shape, the size and thickness of the impeller may vary depending onthe size of a blast wheel assembly and the desired performancecharacteristics. For example, the impeller 14 may have interior orexterior walls that taper in either direction along its axis. Typically,the impeller will be made of a ferrous material, such as cast ormachined iron or steel, although other materials may also beappropriate. In one particular embodiment, the impeller is formed ofcast white iron.

The wheel assembly 18 of the centrifugal blast wheel machine 10 includesa hub or wheel 24 and a plurality of blades, each indicated at 26, tothrow blast media introduced into the wheel assembly to treat the workpiece contained within the housing 12. The arrangement is such that theimpeller 14 is positioned about an axis of the wheel 24 of the wheelassembly 18, with the impeller having a media inlet at one end adaptedto receive blast media and a plurality of impeller media outletsconstructed and arranged to allow egress of blast media upon rotation ofthe impeller. The control cage of the control cage assembly 16 surroundsthe impeller 14 in a position in which the media outlet of the controlcage assembly is adapted for passage of blast media to the heel ends ofthe blades of the blast wheel assembly 18. As mentioned above, the motor20 is coupled to the impeller 14 and to the wheel assembly 18 to drivethe rotation of the impeller and the wheel assembly.

Referring to FIGS. 5 and 6, the present disclosure is directed to thecontrol cage assembly 16 for the abrasive blast wheel assembly 18 thatis configured to lock a control cage of the control cage assembly inplace. In one embodiment, the control cage assembly 16 of the presentdisclosure includes a control cage 28 having a cylindrical wall 30forming a housing defining an interior chamber and a media outlet forallowing the egress of blast media from the interior chamber. A typicalcentrifugal blast wheel machine 10 having a control cage 28 is used totreat a surface (not shown) of a work piece by projecting blast media(not shown) at the surface. The treatment may be in the nature ofcleaning, peening, abrading, eroding, de-burring, de-flashing, and thelike, and the blast media typically consists of solid particles such asshot, grit, segments of wire, sodium bicarbonate, or other abrasives,depending on the surface being treated and/or the material being removedfrom the surface.

The control cage 28 of the control cage assembly 16, typically formed ofcast iron, is positioned concentrically around impeller 14 and, isapproximately cylindrical in shape. Like the impeller 14, however, thecontrol cage 28 may have other shapes, and may, for example, taperinternally and/or externally in either direction along its axis. Thecontrol cage 28 also includes an outer flange or locking ring 34, whichmates with an adaptor plate 36, which in turn is mounted on the wheel 24of the wheel assembly 18, fixing the control cage with respect to thewheel and preventing the control cage from rotating with respect to thewheel upon operation of the blast wheel assembly 10. A retaining ring 38is further provided to firmly secure the locking ring 34 and to preventthe rotational movement of the control cage 28 with respect to theadaptor plate 36 after securing the adaptor plate to the blast wheel 24of the blast wheel assembly 18. The control cage 28 is then locked inplace by placing the feed spout 22 onto the control cage and by firmlysecuring a feed spout 54, which is shown in FIG. 4.

In other embodiments, the control cage 28 may be restrained frommovement by attachment to other stationary elements of the blast wheelassembly 18 or its (as indicated above) environment, or, in some cases,may be allowed to or made to rotate in one or both directions. As shown,one of two retaining rings 38 may be provided, with one of the retainingrings having markings 40 or other indicia that allow a user to positionthe control cage 28 in a certain desired rotational orientation, so asto control the direction of the media being thrown by the blast wheelassembly 18.

As mentioned above, the media outlet 32 of the control cage 28 allowsegress of blast media upon operation of the blast wheel assembly 18. Inthe illustrated embodiment, the media outlet 32 is approximatelyrectangular in shape when viewed from the side (i.e., in a directionperpendicular to its axis) and is approximately ⅗ the height of thecylindrical wall 30 of the control cage 28. The size, shape, andlocation of the media outlet 32 may vary depending on the application,however. The length of the media outlet 32 is measured in degrees, fromthe innermost portion of the opening furthest ahead in the direction ofrotation to the outermost edge of the trailing portion. While the mediaoutlet 32 of the shown embodiment is approximately seventy degrees for awheel rotating in either direction, in other embodiments, the length ofthe opening (in either direction) may vary, depending numerous factorssuch as the overall size of the blast wheel assembly 18, the nature ofthe media being thrown, and the desired rate of flow, as would beunderstood by one of skill in the art.

Referring back to FIGS. 1-3, the wheel assembly 18, which is arrangedconcentrically around control cage 28, includes the plurality of blades26 sandwiched between a rear wheel and a front wheel of the wheel 24 ofthe wheel assembly. The various parts of wheel assembly 18 are typicallyformed of cast iron, although they may also be made of any otherappropriate material and/or method. The wheel assembly 18 is connectedto the motor 20, in this embodiment by means of key inserted to lock ashaft of motor to the rear wheel of the wheel assembly, so that wheelassembly may be rotated by motor during operation of the blast wheelassembly. Blades 26, each of which have a heel end and a tip, areconstructed and arranged to direct the blast media at the surface beingtreated. The blades 26 may be of any suitable size and any suitableshape, including one or more of straight, curved, flared, flat, concave,or convex shapes.

The operation of the centrifugal blast wheel machine 10 is as follows.The blast media is fed from the feed spout 22 into the rotating impeller14. By contact with the rotating impeller vanes (as well as with otherparticles of media already in the impeller 14), the blast mediaparticles are accelerated, giving rise to a centrifugal force that movesthe particles in radial direction, away from the axis of the impeller.The particles, now moving in a generally circular direction as well asoutwards, move through the impeller 14 openings into the space betweenthe impeller and the control cage 28, still being carried by themovement of the impeller vanes and the other particles.

When the particles that have passed though the impeller openings intothe space between the impeller 14 and the control cage 28 to the mediaoutlet 32, the rotational and centrifugal forces move the particlesthrough the media outlet and onto the heel ends of the blades 26. Thecontrol cage 28 functions to meter a consistent and appropriate amountof blast media onto the blades 26. As the blades 26 of the blast wheel24 rotate, the particles are moved along their lengths and accelerateuntil they reach the tips, at which point they are thrown from the endsof the blades toward the work piece.

Referring additionally to FIGS. 7-9, the locking ring 34 of the controlcage assembly 16 is secured to a peripheral edge of the cylindrical wall30. As shown, the locking ring 34 is a separate element that is secured(e.g., by welding) to the cylindrical wall 30 of the control cage 28.The locking ring 34 includes an indicator needle 42 that projectsradially outwardly from the locking ring. The indicator needle 42 can beintegrally formed with the locking ring 34 or be secured to the lockingring as a separate component. The adaptor plate 36 includes a centralopening 44 configured to receive the cylindrical wall 30 of the controlcage 28 therein. The adaptor plate 36 further includes a circumferentialrecess 46 that is sized and shaped to receive the locking ring 34 withthe control cage 28 being inserted into the locking ring and secured bythe retaining ring 38. In one embodiment, the circumferential recess 46is machined in the adaptor plate 36.

The adaptor plate 36 further includes two recesses 48, 50 formedtherein, which are configured to receive the indicator needle 42 whensecuring the locking ring 34 and the control cage 28 to the adaptorplate. Only one recess is accessible to accept the indicator needle 42,based on the wheel assembly 24. In one embodiment, the wheel assembly 24is rotated clockwise with the indicator needle 42 in the recess 48 and aplug 52 placed in recess 50 to prevent accidental assembly. The plug 52may be machined or cast, with an arrow embedded in the plug as anadditional feature to show the wheel assembly 24 rotation. The plug 52may be the same shape as the recess and glued in place with a suitableadhesive, such as Loctite™ H4800. As shown, each recess 48, 50 extendsoutwardly from the circumferential recess 46 and is machined to a depthco-planar with the circumferential recess. Each recess 48, 50 includes arange of movement of the control cage 28 within the locking ring 34. Inone embodiment, the range of movement is color coded so that the personinstalling the control cage assembly 16 sets the control cage 28 withinan allowed set point range. Each recess 48, 50 is designed to provide apositive stop for the indicator needle 42 to prevent further rotationalmovement of the locking ring 34 and the control cage 28 beyond arecommended setting. The arrangement is such that the locking ring 34freely floats between the retaining ring and the adaptor plate 36 untilthe retaining ring 38 is secured in place with suitable fasteners, e.g.,machine screws.

Referring to FIG. 10, the control cage 28 of embodiments of the controlcage assembly 16 of the present disclosure offers a “positive stop” thatis placed on the blast wheel 24 by the adaptor plate 36 to preventincorrect positioning of the control cage. The indicator needle 42 mustbe positioned within the recess 48 or 50 to properly seat the lockingring 34 within the circumferential recess 46 when inserting the controlcage 28 in the central opening 44 of the adaptor plate 36. The controlcage assembly 16 is customized to the specific application and thelocation and the range of movement of the control cage 28 within thelocking ring 34 will generally range from “9 o′clock” (270°) to “3o'clock” (90°) positions as viewed from the control cage retaining ring38. The control cage assembly 16 is configured to provide an easy toread and understand visual reference to the current setting of thecontrol cage/hot spot in relation to the manufacturers recommended setpoint. The assembly is designed to prevent the accidental incorrectsetting of the control cage/hot spot. (Incorrect control cage settingscan adversely affect the hot spot and thus reduce the cleaningefficiency ultimately increasing cost. Additionally, incorrect controlcage settings can direct the hot spot directly into the wheel housingitself causing damage and premature wear of the wheel unit.) The controlcage assembly 16 is designed to prevent the incorrect control cage setpoint.

Having thus described several aspects of at least one embodiment of thisdisclosure, it is to be appreciated various alterations, modifications,and improvements will readily occur to those skilled in the art. Suchalterations, modifications, and improvements are intended to be part ofthis disclosure, and are intended to be within the spirit and scope ofthe disclosure. Accordingly, the foregoing description and drawings areby way of example only.

What is claimed is:
 1. A centrifugal blast wheel machine comprising: awheel assembly having a plurality of blades configured to throw blastmedia introduced into the wheel assembly against a work piece; animpeller positioned about an axis of the wheel assembly, the impellerhaving a media inlet at one end adapted to receive blast media and aplurality of impeller media outlets constructed and arranged to allowegress of blast media upon rotation of the impeller; a motor coupled tothe impeller to drive the rotation of the impeller and the wheelassembly; and a control cage assembly surrounding the impeller andsecured to the wheel assembly, the control cage assembly including acontrol cage having a cylindrical wall defining an interior chamber anda media outlet formed in the cylindrical wall to allow the egress ofblast media from the interior chamber, a locking ring secured to aperipheral edge of the cylindrical wall, the locking ring including anindicator projecting radially outwardly from the locking ring, anadaptor plate secured to the wheel assembly, the adaptor plate includinga central opening configured to receive the cylindrical wall of thecontrol cage therein and at least one recess formed therein configuredto receive the indicator when securing the locking ring and the controlcage to the adaptor plate, and a retaining ring configured to be securedto the adaptor plate and to firmly secure the locking ring and thecontrol cage in place.
 2. The centrifugal blast wheel machine of claim1, wherein the adaptor plate includes a circumferential recess formedtherein, the circumferential recess being configured to receive thelocking ring therein.
 3. The centrifugal blast wheel machine of claim 2,wherein the at least one recess of the adaptor plate extends outwardlyfrom the circumferential recess.
 4. The centrifugal blast wheel machineof claim 1, wherein the at least one recess includes a range of movementof the control cage within the locking ring.
 5. The centrifugal blastwheel machine of claim 4, wherein the range of movement is color coded.6. The centrifugal blast wheel machine of claim 1, wherein the at leastone recess further acts as a positive stop for the indicator needle toprevent further rotational movement of the locking ring beyond arecommended setting.
 7. The centrifugal blast wheel machine of claim 1,wherein the locking ring freely floats between the retaining ring andthe adaptor plate until the retaining ring is secured in place.
 8. Acontrol cage assembly for a centrifugal blast wheel machine, the controlcage assembly comprising: a control cage having a cylindrical walldefining an interior chamber and a media outlet formed in thecylindrical wall to allow the egress of blast media from the interiorchamber; a locking ring secured to a peripheral edge of the cylindricalwall, the locking ring including an indicator projecting radiallyoutwardly from the locking ring; an adaptor plate secured to the wheelassembly, the adaptor plate including a central opening configured toreceive the cylindrical wall of the control cage therein and at leastone recess formed therein configured to receive the indicator whensecuring the locking ring and the control cage to the adaptor plate; anda retaining ring configured to be secured to the adaptor plate and tofirmly secure the locking ring and the control cage in place.
 9. Thecontrol cage assembly of claim 8, wherein the adaptor plate includes acircumferential recess formed therein, the circumferential recess beingconfigured to receive the locking ring therein.
 10. The control cageassembly of claim 9, wherein the at least one recess of the adaptorplate extends outwardly from the circumferential recess.
 11. The controlcage assembly of claim 8, wherein the at least one recess includes arange of movement of the control cage within the locking ring.
 12. Thecontrol cage assembly of claim 11, wherein the range of movement iscolor coded.
 13. The control cage assembly of claim 8, wherein the atleast one recess further acts as a positive stop for the indicatorneedle to prevent further rotational movement of the locking ring beyonda recommended setting.
 14. The control cage assembly of claim 8, whereinthe locking ring freely floats between the retaining ring and theadaptor plate until the retaining ring is secured in place.
 15. A methodof assembling a centrifugal blast wheel machine, the method comprising:providing a control cage having a cylindrical wall having an interiorchamber and a media outlet formed in the cylindrical wall to allow theegress of blast media from the interior chamber; securing a locking ringto a peripheral edge of the cylindrical wall, the locking ring includingan indicator projecting radially outwardly from the locking ring;securing an adaptor plate to the wheel assembly, the adaptor plateincluding a central opening configured to receive the cylindrical wallof the control cage therein and at least one recess formed thereinconfigured to receive the indicator when securing the locking ring andthe control cage to the adaptor plate; positioning the control cagehaving the locking ring on the adaptor plate, and securing a retainingring to the adaptor plate to secure the locking ring and the controlcage in place.
 16. The method of claim 15, wherein the adaptor plateincludes a circumferential recess formed therein, the circumferentialrecess being configured to receive the locking ring therein.
 17. Themethod of claim 16, wherein the at least one recess includes a range ofmovement of the control cage within the locking ring.
 18. The method ofclaim 17, wherein the range of movement is color coded.
 19. The methodof claim 15, wherein the at least one recess further acts as a positivestop for the indicator needle to prevent further rotational movement ofthe locking ring beyond a recommended setting.
 20. The method of claim15, wherein the locking ring freely floats between the retaining ringand the adaptor plate until the retaining ring is secured in place.